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Flatten list of lists [duplicate]
...p evaluates MUCH faster than the unraveled loop and eliminates the append calls!
If you have multiple items in a sublist the list comp will even flatten that. ie
>>> list_of_lists = [[180.0, 1, 2, 3], [173.8], [164.2], [156.5], [147.2], [138.2]]
>>> flattened = [val for sublist...
Switch statement for string matching in JavaScript
...ode would match that in the "xxx.local" branch.
Update: Okay, so technically you can use a switch for substring matching, but I wouldn't recommend it in most situations. Here's how (live example):
function test(str) {
switch (true) {
case /xyz/.test(str):
display("• Matched '...
How do I center floated elements?
...ine-block works cross-browser, even on IE6 as long as the element is originally an inline element.
Quote from quirksmode:
An inline block is placed inline (ie. on the same line as adjacent content), but it behaves as a block.
this often can effectively replace floats:
The real use of th...
Unable to access JSON property with “-” dash
...s answer, note that in Node.js if you access JSON with the array syntax [] all nested JSON keys should follow that syntax
This is the wrong way
json.first.second.third['comment']
and will will give you the 'undefined' error.
This is the correct way
json['first']['second']['third']['comment']
...
How to go up a level in the src path of a URL in HTML?
...
Here is all you need to know about relative file paths:
Starting with / returns to the root directory and starts there
Starting with ../ moves one directory backward and starts there
Starting with ../../ moves two directories backw...
Add EBS to Ubuntu EC2 Instance
...
Thanks a lot for this! I was totally confused by the /mnt directory and wrongly assumed that my extra EBS volume (/dev/xvdf) that I told AWS to attach at instance creation was already mounted. Also, the mapping between what AWS shows (/dev/sdf) and (/dev/xv...
Diff two tabs in Vim
...ng the second file in the same tab instead of a new one.
Here's what I usually do:
:edit file1
:diffthis
:vnew
:edit file2
:diffthis
The :vnew command splits the current view vertically so you can open the second file there. The :diffthis (or short: :difft) command is then applied to each view.
...
Moment.js: Date between dates
...
For React after npm install moment, import moment from 'moment';
– John
2 days ago
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show...
Which equals operator (== vs ===) should be used in JavaScript comparisons?
...
The strict equality operator (===) behaves identically to the abstract equality operator (==) except no type conversion is done, and the types must be the same to be considered equal.
Reference: Javascript Tutorial: Comparison Operators
The == operator will compare for equ...
NSUserDefaults removeObjectForKey vs. setObject:nil
... *keys = [[[NSUserDefaults standardUserDefaults] dictionaryRepresentation] allKeys] copy];
for(NSString *key in keys) {
NSLog(@"Key Name: %@", key);
}
[keys release];
or simply dump the key/value dictionary of NSUserDefaults standardUserDefaults
NSLog(@"All contents of NSUserDefaults: %...